<?php // $Id: lib.php,v 1.4.2.6 2008/10/14 20:32:47 skodak Exp $

///////////////////////////////////////////////////////////////////////////
//																	   //
// NOTICE OF COPYRIGHT												   //
//																	   //
// Moodle - Modular Object-Oriented Dynamic Learning Environment		 //
//		  http://moodle.com											//
//																	   //
// Copyright (C) 1999 onwards  Martin Dougiamas  http://moodle.com	   //
//																	   //
// This program is free software; you can redistribute it and/or modify  //
// it under the terms of the GNU General Public License as published by  //
// the Free Software Foundation; either version 2 of the License, or	 //
// (at your option) any later version.								   //
//																	   //
// This program is distributed in the hope that it will be useful,	   //
// but WITHOUT ANY WARRANTY; without even the implied warranty of		//
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the		 //
// GNU General Public License for more details:						  //
//																	   //
//		  http://www.gnu.org/copyleft/gpl.html						 //
//																	   //
///////////////////////////////////////////////////////////////////////////
/**
 * File in which the overview_report class is defined.
 * @package gradebook
 */

require_once($CFG->dirroot . '/grade/report/lib.php');
require_once($CFG->libdir.'/tablelib.php');

/**
 * Class providing an API for the overview report building and displaying.
 * @uses grade_report
 * @package gradebook
 */
class grade_report_overview extends grade_report {

	/**
	 * The user.
	 * @var object $user
	 */
	var $user;

	/**
	 * A flexitable to hold the data.
	 * @var object $table
	 */
	var $table;

	/**
	 * show student ranks
	 */
	var $showrank;

	/**
	 * Constructor. Sets local copies of user preferences and initialises grade_tree.
	 * @param int $userid
	 * @param object $gpr grade plugin return tracking object
	 * @param string $context
	 */
	function grade_report_overview($userid, $gpr, $context) {
		global $CFG, $COURSE;
		parent::grade_report($COURSE->id, $gpr, $context);

		$this->showrank = grade_get_setting($this->courseid, 'report_overview_showrank', !empty($CFG->grade_report_overview_showrank));

		// get the user (for full name)
		$this->user = get_record('user', 'id', $userid);

		// base url for sorting by first/last name
		$this->baseurl = $CFG->wwwroot.'/grade/overview/index.php?id='.$userid;
		$this->pbarurl = $this->baseurl;

		$this->setup_table();
	}

	/**
	 * Prepares the headers and attributes of the flexitable.
	 */
	function setup_table() {
		/*
		 * Table has 3 columns
		 *| course  | final grade | rank (optional) |
		 */

		// setting up table headers
		if ($this->showrank) {
			$tablecolumns = array('coursename', 'grade', 'rank');
			$tableheaders = array($this->get_lang_string('coursename', 'grades'),
								  $this->get_lang_string('grade'),
								  $this->get_lang_string('rank', 'grades'));
		} else {
			$tablecolumns = array('coursename', 'grade');
			$tableheaders = array($this->get_lang_string('coursename', 'grades'),
								  $this->get_lang_string('grade'));
		}
		$this->table = new flexible_table('grade-report-overview-'.$this->user->id);

		$this->table->define_columns($tablecolumns);
		$this->table->define_headers($tableheaders);
		$this->table->define_baseurl($this->baseurl);

		$this->table->set_attribute('cellspacing', '0');
		$this->table->set_attribute('id', 'overview-grade');
		$this->table->set_attribute('class', 'boxaligncenter generaltable');

		$this->table->setup();
	}

	function fill_table() {
		global $CFG;

		// MDL-11679, only show 'mycourses' instead of all courses
		if ($courses = get_my_courses($this->user->id, 'c.sortorder ASC', 'id, shortname, showgrades')) {
			$numusers = $this->get_numusers(false);

			foreach ($courses as $course) {
				if (!$course->showgrades) {
					continue;
				}
				$courselink = '<a href="'.$CFG->wwwroot.'/grade/report/user/index.php?id='.$course->id.'">'.$course->shortname.'</a>';
				$canviewhidden = has_capability('moodle/grade:viewhidden', get_context_instance(CONTEXT_COURSE, $course->id));

				// Get course grade_item
				$course_item = grade_item::fetch_course_item($course->id);

				// Get the stored grade
				$course_grade = new grade_grade(array('itemid'=>$course_item->id, 'userid'=>$this->user->id));
				$course_grade->grade_item =& $course_item;
				$finalgrade = $course_grade->finalgrade;

				if (!$canviewhidden and !is_null($finalgrade)) {
					if ($course_grade->is_hidden()) {
						$finalgrade = null;

					} else {
						// This is a really ugly hack, it will be fixed in 2.0
						$items = grade_item::fetch_all(array('courseid'=>$course->id));
						$grades = array();
						$sql = "SELECT g.*
								  FROM {$CFG->prefix}grade_grades g
								  JOIN {$CFG->prefix}grade_items gi ON gi.id = g.itemid
								 WHERE g.userid = {$this->user->id} AND gi.courseid = {$course->id}";
						if ($gradesrecords = get_records_sql($sql)) {
							foreach ($gradesrecords as $grade) {
								$grades[$grade->itemid] = new grade_grade($grade, false);
							}
							unset($gradesrecords);
						}
						foreach ($items as $itemid=>$unused) {
							if (!isset($grades[$itemid])) {
								$grade_grade = new grade_grade();
								$grade_grade->userid = $this->user->id;
								$grade_grade->itemid = $items[$itemid]->id;
								$grades[$itemid] = $grade_grade;
							}
							$grades[$itemid]->grade_item =& $items[$itemid];
						}
						$hiding_affected = grade_grade::get_hiding_affected($grades, $items);
						if (array_key_exists($course_item->id, $hiding_affected['altered'])) {
							$finalgrade = $hiding_affected['altered'][$course_item->id];

						} else if (!empty($hiding_affected['unknown'][$course_item->id])) {
							$finalgrade = null;
						}

						unset($hiding_affected);
						unset($grades);
						unset($items);
					}
				}

				$data = array($courselink, grade_format_gradevalue($finalgrade, $course_item, true));

				if (!$this->showrank) {
					//nothing to do

				} else if (!is_null($finalgrade)) {
					/// find the number of users with a higher grade
					/// please note this can not work if hidden grades involved :-( to be fixed in 2.0
					$sql = "SELECT COUNT(DISTINCT(userid))
							  FROM {$CFG->prefix}grade_grades
							 WHERE finalgrade IS NOT NULL AND finalgrade > $finalgrade
								   AND itemid = {$course_item->id}";
					$rank = count_records_sql($sql) + 1;

					$data[] = "$rank/$numusers";

				} else {
					// no grade, no rank
					$data[] = '-';
				}

				$this->table->add_data($data);
			}
			return true;

		} else {
			notify(get_string('nocourses', 'grades'));
			return false;
		}
	}

	/**
	 * Prints or returns the HTML from the flexitable.
	 * @param bool $return Whether or not to return the data instead of printing it directly.
	 * @return string
	 */
	function print_table($return=false) {
		ob_start();
		$this->table->print_html();
		$html = ob_get_clean();
		if ($return) {
			return $html;
		} else {
			echo $html;
		}
	}

	/**
	 * Processes the data sent by the form (grades and feedbacks).
	 * @var array $data
	 * @return bool Success or Failure (array of errors).
	 */
	function process_data($data) {
	}
}

function grade_report_overview_settings_definition(&$mform) {
	global $CFG;

	$options = array(-1 => get_string('default', 'grades'),
					  0 => get_string('hide'),
					  1 => get_string('show'));

	if (empty($CFG->grade_overviewreport_showrank)) {
		$options[-1] = get_string('defaultprev', 'grades', $options[0]);
	} else {
		$options[-1] = get_string('defaultprev', 'grades', $options[1]);
	}

	$mform->addElement('select', 'report_overview_showrank', get_string('showrank', 'grades'), $options);
	$mform->setHelpButton('report_overview_showrank', array('showrank', get_string('showrank', 'grades'), 'grade'));
}

?>
